export default {
  namespaced:true,
  
  // 模块的 state 数据
  state:()=>({
    // 购物车的数组，用来存储购物车中每个商品的信息对象
    // 每个商品的信息对象，都包含如下 6 个属性：
    // { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
    cart: JSON.parse(uni.getStorageSync('cart') || '[]')
  }),
  //模块的 mutations 方法
  mutations:{
    addToCart(state,goods){
     const findResult =  state.cart.find(x=>x.goods_id === goods.goods_id)
     if(!findResult){
       state.cart.push(goods)
     }else{
        findResult.goods_count++
     }
     
     this.commit('m_cart/savaToStorage')
    },
    // 持久化vuex存储的数据
    savaToStorage(state){
      uni.setStorageSync('cart',JSON.stringify(state.cart))
    },
    // 更新购物车中勾选状态
    updateGoodsStatus(state,goods){
      const findResult =  state.cart.find(x=>x.goods_id === goods.goods_id)
      if(findResult){
        findResult.goods_status = goods.goods_status
        this.commit('m_cart/savaToStorage')
      }
    },
    // 更新商品数量
    updateGoodsCount(state,goods){
      const findResult = state.cart.find(x=>x.goods_id === goods.goods_id)
      if(findResult){
        findResult.goods_count = goods.goods_count
        this.commit('m_cart/savaToStorage')
      }
    },
    // 根据id删除对应的商品
    removeGoodsById(state,goods_id){
      state.cart = state.cart.filter(x=>x.goods_id !== goods_id)
      this.commit('m_cart/savaToStorage')
    },
    // 更新所有商品勾选状态
    updateAllGoodsStatus(state,newstatus){
      state.cart.forEach(x=>x.goods_status = newstatus)
      this.commit('m_cart/savaToStorage')
    }
  },
  // 模块的 getters 属性
  getters:{
    // 购物车中所有商品的总数量
    total(state){
      // let c= 0
      // state.cart.forEach(x => c += x.goods_count)
      // return c
      
      return state.cart.reduce((total,item)=>total += item.goods_count,0)
    },
    // 购物车中已勾选的商品总数量
    checkedCount(state){
     return state.cart.filter(x=>x.goods_status).reduce((total,item)=> total += item.goods_count,0)
    },
    // 已勾选的商品总价
    checkGoodsAmount(state){
     return state.cart.filter(x=>x.goods_status).reduce((total,item)=>total+=item.goods_count * item.goods_price,0).toFixed(2)
    }
  }
}